Many manufacturing processes require a constant supply of compressed gasses, such as compressed air. Compressed air may be used for many applications, for example, the actuation and control of pneumatic valves, air operated cylinders, controllers, operation of process machinery, pneumatically operated tooling, as a transport media for conveying bulk solids, or as a purge gas. Oil lubricated rotary air compressors of various types are commonly applied for generating a compressed air source for various applications.
One well known problem with compressed air systems is that a small amount of the compressor lubricating oil may become entrained into the compressed gas during the air compression process. It is desirable to remove the entrained oil from the compressed air supply to minimize the loss of lubricating oil as well as to reduce the chance of contamination of other downstream equipment and processes utilizing the compressed air. In attempts to overcome this issue various types of air/oil separators have been developed over the years. One example, U.S. Pat. No. 5,800,584 discloses a typical oil separator for separating oil from oil-laden compressed air that has one or more oil coalescing elements arranged on a support body inside of a housing. Another example is U.S. Pat. No. 4,632,682 that discloses a cartridge type air/oil separator and filter.
Another problem in air/oil separators is that the coalescing media tends to become saturated with oil during use thereby resulting in increased pressure drop across the air/oil separator due to blockage of a portion of the pores in the media. An additional problem arises in that the amount of oil carryover after the air/oil separator may still be too high for many applications.
As can be seen, there remains a need for an improved air/oil separator that reduces the amount of oil carryover, is effective in reducing oil saturation of the coalescing elements and reduces differential pressure drop across the air/oil separator.